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61.
T Shimizu I Narabayashi Y Ogura Y Uesugi K Tabuchi R Namba Y Nakata R Matsui K Sueyoshi T Kawai 《Canadian Metallurgical Quarterly》1995,13(3):109-113
The purpose of this study was to evaluate the clinical usefulness of three-dimensional (3D) images of the bronchi obtained using helical CT. Thirteen patients with lung cancer, one with tracheal diverticulum, and one with bronchial amyloidosis were examined. The CT scanner employed was the Toshiba Xforce. The helical CT scan cycle consisted of 20 continuous rotations, each requiring 1.5 sec, for a total scanning time of 30 sec. Scans were obtained using a 5-mm X-ray beam width, a 5-mm/1.5 sec couchtop sliding speed, and a 2-mm reconstruction interval. 3D images were reconstructed using a CEMAX VIPstation. The optimal lower and upper threshold CT values for 3D images of the bronchi were -650 and -100 HU, respectively, and 3D images clearly depicted endobronchial lesions. Cartilage crescents were also demonstrated, but longitudinal and circular mucosal folds could not be visualized. In conclusion, 3D images of the bronchi acquired using helical CT were useful in evaluating endobronchial lesions. 相似文献
62.
Yuichiro Ezoe Ikuyuki Mitsuishi Utako Takagi Masaki Koshiishi Kazuhisa Mitsuda Noriko Y. Yamasaki Takaya Ohashi Fumiki Kato Susumu Sugiyama Raul E. Riveros Hitomi Yamaguchi Shinya Fujihira Yoshiaki Kanamori Kohei Morishita Kazuo Nakajima Ryutaro Maeda 《Microsystem Technologies》2010,16(8-9):1633-1641
We are developing novel ultra light-weight and high-resolution X-ray micro pore optics for space X-ray telescopes. In our method, curvilinear micro pore structures are firstly fabricated by silicon deep reactive ion etching (DRIE) or X-ray LIGA processes. Secondly, side walls of the micro structures are smoothed by magnetic field assisted finishing and/or hydrogen annealing techniques for high reflectivity mirrors. Thirdly, to focus parallel X-ray lights from astronomical objects, these structures are elastically or plastically bent into a spherical shape. Fourthly, the bent structures are stacked to form a multi-stage X-ray telescope. In this paper, we report on fabrication and X-ray reflection tests of silicon and nickel X-ray mirrors using the DRIE and LIGA processes, respectively. For the first time, X-ray reflections were confirmed on both of the mirrors. Estimated rms roughnesses were 5 nm and 3 nm for the silicon and nickel mirrors, respectively. 相似文献
63.
Masaru Ogura Susumu Kage Masayoshi Hayashi Masahiko Matsukata Eiichi Kikuchi 《Applied catalysis. B, Environmental》2000,27(4):L213-L216
Effect of second components on the catalytic performance of Pd/H-ZSM-5 zeolite (Pd: 0.4 wt.%) was evaluated by a durability test of NO reduction with CH4 at a relatively high temperature of 500°C in the presence of water vapor for a prolonged period. The Pd/H-ZSM-5 showed high stable activity for this reaction without H2O in the reactant feed, while immediate and irreversible deactivation was observed in the presence of H2O, resulting in no activity after 7 h. The second components such as Co, Rh, Ag, Ce, and Fe introduced individually to the Pd/H-ZSM-5 enhanced the durability, and in particular the addition of 3.3 wt.% Co led to a stable NO conversion for more than 40 h in the presence of H2O. 相似文献
64.
Sorapong Pavasupree Jaturong Jitputti Susumu Yoshikawa 《Materials Research Bulletin》2008,43(1):149-157
Mesoporous anatase TiO2 nanopowder was synthesized by hydrothermal method at 130 °C for 12 h. The samples were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), selected-area electron diffraction (SAED), HRTEM, and Brunauer-Emmett-Teller (BET) surface area. The as-synthesized sample with narrow pore size distribution had average pore diameter about 3-4 nm. The specific BET surface area of the as-synthesized sample was about 193 m2/g. Mesoporous anatase TiO2 nanopowders (prepared by this study) showed higher photocatalytic activity than the nanorods TiO2, nanofibers TiO2 mesoporous TiO2, and commercial TiO2 nanoparticles (P-25, JRC-01, and JRC-03). The solar energy conversion efficiency (η) of the cell using the mesoporous anatase TiO2 was about 6.30% with the short-circuit current density (Jsc) of 13.28 mA/cm2, the open-circuit voltage (Voc) of 0.702 V and the fill factor (ff) of 0.676; while η of the cell using P-25 reached 5.82% with Jsc of 12.74 mA/cm2, Voc of 0.704 V and ff of 0.649. 相似文献
65.
66.
Compound classes in coal liquids were investigated by thin-layer chromatography coupled with a flame ionization detector (t.l.c.-f.i.d.). Individual t.l.c. peaks for coal liquids were identified as paraffins, aromatics, polar compounds and more strongly polar compounds or asphaltenes in order of increasing Rf values by comparison with specific compounds separated previously by conventional liquid chromatography. Concentrations of compound classes for a series of samples obtained by varying the hydrogenation time were estimated and good agreement was found with the results obtained by the USBM-API 60 liquid chromatography procedure. By using the t.l.c.-f.i.d. method, the relation of distribution of compound classes to the reaction conditions of coal hydrogenation could be derived quantitatively with relative ease. 相似文献
67.
We report research on the development of a method of fabricating three-dimensional microstructures that uses synchrotron radiation light. Some research on three-dimensional processing methods using SR lithography has already been reported. They have involved techniques of applying exposure energy distributions to resist surfaces. Complicated energy distributions need to be applied to resist surfaces to fabricate arbitrary three-dimensional structures. However, we devised a new method that made it possible to fabricate arbitrary three-dimensional microstructures by using a mask with pattern created function. The advantages of this method are that it is suitable for rapid prototyping and it reduces the fabrication time and cost since it is not necessary to fabricate conventional photolithographic masks. Our research involved a basic experiment on this method of fabrication where we succeeded in fabricating a free-form surface by exposing it through an overlapping array of pixels that created a single aperture. Moreover, the pixel size could be made smaller than the aperture size by overlapping adjoining pixels. 相似文献
68.
This paper describes an unusual behavior detection system based on an omnidirectional vision sensor, as one of the important elements in realizing “Sensing and Robotic Support Rooms” for elderly people. Such support rooms are expected to be further developed in the future with advanced abilities to automatically recognize elderly people's actions and behavior patterns, to detect unusual patterns by using sensors, and to support their daily motions by using robotic manipulator control systems. The proposed monitoring system using an omnidirectional vision sensor automatically learns daily behavior patterns and detects unusual behavior patterns and actions by using the Bayesian network approach. The Bayesian network is constructed by using image feature values such as area and center‐of‐gravity values extracted from a captured image sequence, and the respective behavior patterns are represented as conditional probabilities. Unusual behavior patterns can be automatically detected on the basis of the low generation probability values. Experiments based on the investigation of elderly people's typical daily behavior patterns have shown the effectiveness of the proposed system. © 2010 Wiley Periodicals, Inc. Electr Eng Jpn, 172(3): 42–51, 2010; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.20990 相似文献
69.
Shinji Yamashita Susumu Kanno Ayako Honjo Yurika Otoki Kiyotaka Nakagawa Mikio Kinoshita Teruo Miyazawa 《Lipids》2016,51(2):199-210
Ethanolamine plasmalogen (PlsEtn), which is present at high levels in brains, is believed to be involved in neuronal protection. The present study was performed to search for PlsEtn resources in foodstuffs. The foodstuffs examined showed a wide range of PlsEtn contents from 5 to 549 μmol/100 g wet wt. The marine invertebrates, blue mussel, and ascidian had high PlsEtn contents (over 200 μmol/100 g wet wt). Profiling of the molecular species showed that the predominant fatty acids of PlsEtn species were 20:5 (EPA) and 22:6 (DHA) at the sn‐2 position of the glycerol moiety in marine foodstuffs, whereas major PlsEtn species in land foodstuffs were 20:4. Following quantitative analysis by multiple reaction monitoring, the ascidian viscera were shown to contain the highest levels of 18:0/20:5‐PlsEtn and 18:0/22:6‐PlsEtn (86 and 68 μmol/100 g wet wt, respectively). In order to evaluate a neuronal antiapoptotic effect of these PlsEtn species, human neuroblastoma SH‐SY5Y cells were treated with ethanolamine glycerophospholipid (EtnGpl), purified from the ascidian viscera, under serum starvation conditions. Extrinsic EtnGpl from ascidian viscera showed stronger suppression of cell death induced by serum starvation than with bovine brain EtnGpl. The EtnGpl from ascidian viscera strongly suppressed the activation of caspase 3. These results suggest that PlsEtn, especially that containing EPA and DHA, from marine foodstuffs is potentially useful for a therapeutic dietary supplement preventing neurodegenerative diseases, such as Alzheimer's disease (AD). 相似文献
70.
Yukari Tsumura Susumu Ishimitsu Isao Saito Hiroshi Sakai Yukari Kobayashi Yasuhide Tonogai 《Food Additives & Contaminants》2001,18(5):449-460
Plasticizers in duplicate diet samples obtained over 1 week were analysed in order to estimate daily intake. The phthalate esters were as follows: diethyl, dipropyl, dibutyl, dipentyl, dihexyl, butylbenzyl, dicyclohexyl, di(2-ethylhexyl), dioctyl, diisooctyl (mixture of isomers) and diisononyl (mixture). Di(2-ethylhexyl) adipate was also determined. Homogenized samples of composite meals were extracted with acetonitrile, lipids were removed by extraction into n-hexane and the acetonitrile layer was cleaned using FlorisilR and R Bondesil PSA dual layer column. Phthalates were determined by GC/MS (SIM). Phthalate recovery from the fortified food mixture by this method was 62.5-140.8%. Quality assurance as assessed by three laboratories indicated coefficient of variance in the levels of detected phthalates in same lot samples as below 10%. Detection limits were 0.1-23ng/g for each phthalate. One-week duplicate diet samples provided by three hospitals in three remote prefectures of Japan were analysed as individual meals. In all 63 samples, DEHP was present at the highest level among all phthalates in the range 10-4400ng/g. The intake of plasticizers estimated from all samples was 519 µ g DEHP/day, 86 µ g DEHA/day, 65 µ g DINP/day, and 4.7 µ g BBP/day. Calculated DEHP in 2-day samples out of 21 days exceeded EU TDI for a person of 50kg body weight (1850 µ g per day). Disposable PVC gloves used during the preparation of meals were suspected as the source of the high DEHP content. One-day intake of the other phthalates and DEHA was below 7% of TDI in all cases. High concentrations of DEHP (5990ng/g) was found in baby food used in quality assurance work. The source of contamination was the PVC-tube used during production and was effectively reduced by replacing the tube by one made of stainless steel. 相似文献